In the early 1950s, Syd Albrittain came home from Army service in the Korean War with a Silver Star, the military’s third-highest combat award for valor. He tucked it away in a drawer and rarely, if ever, mentioned it. Most of his friends and family knew nothing about it until after he died.

Ten years ago, when Arlington County’s Bishop Denis J. O’Connell High School wanted to acknowledge Mr. Albrittain’s $1 million gift by naming its new academic support center for him, he demurred. He wanted no public thanks or attention.

In his business life, too, Mr. Albrittain operated below the radar, but he left his mark on the area in a lasting way.

Having fulfilled his military obligation, the 6-foot-2 former college football lineman went into the construction and development business as an executive with the Dittmar Co. At the time, parts of Arlington were still reminiscent of the bucolic Virginia countryside.

He began a career that over the decades would help reshape the county into the urbanized amalgam of residential subdivisions, condominiums, apartments, offices, hotels and restaurants that it is today.

Mr. Albrittain, 82, died of cardiac arrest June 5 at the Jefferson, an assisted living facility in Arlington. The death was confirmed by a daughter, Nancy Albrittain Bright.

At his death, Mr. Albrittain was the chief executive of Dittmar. Under his leadership, the company built at least 10,000 properties, including apartment and condominium units, hotels and office buildings, many near Metrorail stops along the Rosslyn-Ballston corridor. It also developed thousands of homes in subdivisions throughout Northern Virginia.

As a developer, Mr. Albrittain followed the wishes of the Arlington County government to support and encourage high-density development near Metrorail stops. Mary Margaret Whipple (D), a former Virginia state senator and past chairwoman of the Arlington County Board, called him “a public-spirited developer who tried to have his buildings fit into the community.”

In addition to overseeing Dittmar, Mr. Albrittain gave away millions of dollars to the Catholic Archdiocese of Arlington, Virginia Hospital Center, the Arlington Free Clinic and other charities.

The fourth of eight children, Sydney Emmanuel Albrittain was born June 21, 1929, in Glen Burnie. His parents later opened a general store in the Southern Maryland community of Bel Alton, where Mr. Albrittain worked during off-school hours.

He graduated from La Plata High School and in 1951 from what is now McDaniel College in Westminster, Md. After college, he led an infantry platoon in combat operations during the Korean War.

He subsequently joined Dittmar, founded by Thomas J. Offutt, and directed the company’s construction operations. In 1986, after Offutt’s death, Mr. Albrittain took charge of the company. He made decisions on what land to buy and what to build on it. He was working until two months before his death.

In 1954, Mr. Albrittain married Gloria Mackin of Baltimore. Besides his wife, survivors include eight children; three sisters; 21 grandchildren; and two great-grandchildren.

On their wedding trip, Mr. Albrittain made a special stop in New York to call on the parents of a soldier who had been killed in Korea. The war had been over for a year, and Mr. Albrittain was no longer in the Army. But the soldier had been a member of his platoon. As his former commanding officer, Mr. Albrittain told his bride he felt a moral obligation to make the call.

He rarely discussed his war experiences.

His friend William D. Dolan III, who served as Mr. Albrittain’s attorney and is a past president of the Virginia State Bar, didn’t know anything about Mr. Albrittain’s Silver Star until someone told him at the wake.

Even close family members didn’t know about the medal until it came up in a casual conversation a few years ago.

Mr. Albrittain was awarded the Silver Star for leading a counterattack on Oct. 8, 1952, after a U.S outpost had been overrun by enemy forces.

According to the citation, then-First Lt. Albrittain led his men “with such ferocity that the enemy were completely routed. The outstanding leadership and devotion to duty . . . by Lieutenant Albrittain were a great source of inspiration to all who witnessed.”